Potent Benzodiazepine Research Articles

The emergence of bromazolam in Jefferson County, AL: a case series.

Postmortem toxicology is an ever-changing landscape presenting challenges for toxicologists and medical examiners. Trends can vary for certain benzodiazepines. While diazepam use tends to remain constant, alprazolam and clonazepam ebb and flow depending on prescription trends and street popularity. Novel benzodiazepines like etizolam vary in casework depending on legal restrictions and black market availability. In May 2022, the first case of the designer benzodiazepine, bromazolam, was detected in Jefferson County Coroner/Medical Examiner's Office casework. Between then and December 2023, an additional nine cases have been observed. Bromazolam is the brominated analog of the low-dose benzodiazepine, alprazolam, and is likely similar in potency. As bromazolam is a potent benzodiazepine, low concentrations of this novel drug are likely to contribute to central nervous system depression in opioid overdose cases. We present 10 cases in which bromazolam was detected in postmortem samples at the University of Alabama at Birmingham toxicology laboratory. The decedents ranged in age from 20 to 41 years. Most of the decedents were White (n = 8; 80%) and male (n = 7; 70%). Bromazolam concentrations ranged from 21 to 3220 ng/mL (mean 401 ng/mL). All but one case were polydrug, and all deaths were related to drug toxicity. Fentanyl was detected in 8 of the 10 decedents, with concentrations ranging from <2.5 to 97 ng/mL (mean 30 ng/mL). Additional drugs detected were methamphetamine, ethanol, oxycodone, methadone, cocaine, amphetamine, morphine, and diphenhydramine. While all manners of death were ruled as accidental, bromazolam was included in the cause of death statements in 9 of the 10 cases. Capturing important emerging drug trends in the death certificate is critical to help inform public health and medical colleagues for preventive measures and treatment in the continued drug epidemic.

Detection of Flunitrazepam in Biological Fluids and Beverages:A Review

AbstractFlunitrazepam, a very potent benzodiazepine with sedative, hypnotic and amnesic effects, is commonly used to treat severe insomnia and as an anesthetic. Due to these characteristics, when flunitrazepam is sneaked into alcohol or drinks, it is often highly associated with violent behavior and drug rape cases. Therefore, it is also known as a “date rape drug”, and the detection of flunitrazepam and its metabolites is of great interest in forensic medicine and pharmacotoxicology. This paper describes the mechanism of action and drug metabolism process of flunitrazepam, reviews the different methods for detecting flunitrazepam published over the years, summarizes the detection limits of each method and compares their advantages and disadvantages. We hope to provide some inspiration for future research in this field.

High-potency benzodiazepine misuse in opioid-dependent patients: use naloxone with care

The misuse of highly potent benzodiazepines is increasing in the UK, particularly among the opioid-using population in Scotland. Differentiating opioid from benzodiazepine toxicity is not always straightforward in patients with...

Evaluation of the sedative effect of sublingual lorazepam versus placebo in patients underwent endoscopy: a double-blind, randomized controlled clinical trial.

Digestive endoscopy (DE) is uncomfortable for most patients. Lorazepam is a potent benzodiazepine with anxiolytic and sedative effects. This study aims to determine the sedative effect of sublingual lorazepam versus placebo as a premedication in patients who underwent DE. This is a mono-center, double-blind, and randomized controlled trial. A lorazepam sublingual tablet was made by researchers and physical tests were done on it, then the double-blind placebo-controlled trial was done to investigate the efficacy of 2 mg sublingually administered lorazepam as a premedication for endoscopy. Lorazepam or a placebo tablet was administered sublingually 30 min before the endoscopy. The patients, nurses, and physicians were blinded to the patient group. The depth of sedation was evaluated according to the American Society of Anesthesiology. In all, 116 patients were randomly assigned to take either lorazepam (n = 58) or a placebo (n = 58). The results of physical properties tests were acceptable according to United States Pharmacopeia. There were no statistical differences between groups regarding age and gender. In the lorazepam group, 75.8% of patients showed mild sedation, and 24.2% of patients showed no sedation. All of the patients in the placebo had no sedation (p = 0.001). Time of procedure (p < 0.001), intraoperative O2 saturation (p < 0.001), intraoperative heart rate (p < 0.001), and intraoperative blood pressure (p < 0.001) were significantly lower in the lorazepam group. No significant or dangerous side effects were observed except a bit of giddiness and dizziness. The results of this study showed that prescription of sublingual lorazepam 25-30 min before endoscopy provided mild sedation. IRCT201611039014N130 (05/11/2016); https://en.irct.ir/trial/9568.

Pristup baziran na Dizajnu eksperimenata za poboljšanje procesa suvog mešanja u proizvodnji tableta sa niskom dozom Alprazolama uz primenu Raman spektroskopije za praćenje uniformnosti sadržaja

A low-dose tablet formulation, containing a potent Benzodiazepine derivative Alprazolam was developed, considering the achievement of appropriate content uniformity of the active substance in powder blends and tablets as a major challenge. Two different types of lactose monohydrate (Tablettose 80 and Granulac 200) and two different types of dry mixing processes (high-shear mixing and "in bulk" mixing) were employed. To evaluate the influence of the variables (mixing speed, mixing time, filling level of the high-shear and cube mixer, lactose monohydrate type) and their interactions upon the response (content uniformity of Alprazolam in the powder blends), a Factorial 2 4 design (with 4 factors at 2 levels in 1 block) was generated for each type of mixer. For high-shear dry mixing the Response Surface, D-optimal Factorial 2 4 design (with 2 replications and 31 experiments) was used, while for the "in bulk" dry mixing the Response Surface, Central Composite Factorial 2 4 design (with 34 experiments) was used. The process parameters for the high-shear mixer were varied within the following ranges: filling level of 70-100%, impeller mixing speed of 50-300 rpm and mixing time of 2-10 minutes. For the cube mixer the following process parameter ranges were employed: filling level of 30-60%, mixing speed of 20-390 rpm and mixing time of 2-10 minutes. Raman spectroscopy in conjunction with a validated Partial Least Square (PLS) regression model was used as a Process Analytical Technology (PAT) tool for Alprazolam content determination and content uniformity monitoring. The DoE model was further employed to optimize the powder blending process in regard to the achievement of appropriate Alprazolam content uniformity using high-shear mixing and Tabletosse 80 as filler. The desirability function revealed that the following process parameters: a mixing time of 2 minutes, a mixing speed of 300 rpm and a 70% filling level of the mixer would produce powder blends with the lowest variability in Alprazolam content. The three independent lab batches of low-dose Alprazolam tablets, produced with high-shear mixing using these process parameters, conformed to the requirements of the European Pharmacopoeia for content (assay) of Alprazolam and uniformity of the dosage units.

Midazolam Prevents the Adverse Outcome of Neonatal Asphyxia.

Birth asphyxia (BA) is the most frequent cause of neonatal death as well as central nervous system (CNS) injury. BA is often associated with neonatal seizures, which only poorly respond to anti-seizure medications and may contribute to the adverse neurodevelopmental outcome. Using a non-invasive rat model of BA, we have recently reported that the potent benzodiazepine, midazolam, prevents neonatal seizures in ~50% of rat pups. In addition to its anti-seizure effect, midazolam exerts anti-inflammatory actions, which is highly relevant for therapeutic intervention following BA. The 2 major aims of the present study were to examine (1) whether midazolam reduces the adverse outcome of BA, and (2) whether this effect is different in rats that did or did not exhibit neonatal seizures after drug treatment. Behavioral and cognitive tests were performed over 14months after asphyxia, followed by immunohistochemical analyses. All vehicle-treated rats had seizures after asphyxia and developed behavioral and cognitive abnormalities, neuroinflammation in gray and white matter, neurodegeneration in the hippocampus and thalamus, and hippocampal mossy fiber sprouting in subsequent months. Administration of midazolam (1 mg/kg i.p.) directly after asphyxia prevented post-asphyctic seizures in ~50% of the rats and resulted in the prevention or decrease of neuroinflammation and the behavioral, cognitive, and neurodegenerative consequences of asphyxia. Except for neurodegeneration in the thalamus, seizures did not seem to contribute to the adverse outcome of asphyxia. The disease-modifying effect of midazolam identified here strongly suggests that this drug provides a valuable option for improving the treatment and outcome of BA. ANN NEUROL 2023;93:226-243.

Discovery of a lead series of potent benzodiazepine 5-HT2C receptor agonists with high selectivity in functional and binding assays

A series of potential new 5-HT2 receptor scaffolds based on a simplification of the clinically studied, 5-HT2CR agonist vabicaserin, were designed. An in vivo feeding assay early in our screening process played an instrumental part in the lead identification process, leading us to focus on a 6,5,7-tricyclic scaffold. A subsequent early SAR investigation provided potent agonists of the 5-HT2C receptor that were highly selective in both functional and binding assays, had good rat PK properties and that significantly reduced acute food intake in the rat.

Interactions of benzodiazepines with heroin: Respiratory depression, temperature effects, and behavior

Benzodiazepines are important therapeutic drugs, but they are often abused and co-abused with opioids. Clinical evidence suggests that benzodiazepines can inhibit respiration, and when combined with the respiratory-depressive effects of opioids, may increase likelihood of death. In this study we used oxygen sensors coupled with high-speed amperometry and multi-site thermorecording to examine how intravenous (iv) midazolam, a potent benzodiazepine, modulates the brain hypoxic and temperature effects of iv heroin in freely-moving rats. Oxygen levels and brain temperature were assessed with high temporal resolution in the nucleus accumbens (NAc), an important structure in the motivational-reinforcement circuit. When administered alone, midazolam (2 mg/kg) modestly decreased NAc temperature but had no evident effects on oxygen levels in this structure. In contrast, heroin (0.4 mg/kg) induced a strong decrease in NAc oxygen that was followed by a weaker, rebound-like oxygen increase. Midazolam pretreatment did not affect heroin-induced brain hypoxia but potentiated the initial hypothermia induced by heroin. However, co-administration of these drugs potentiated the heroin-induced oxygen decrease and enhanced heroin-induced brain hypothermia. Co-administration of heroin and midazolam also resulted in enhanced locomotor inhibition and loss of motor control. This effect caused some rats to collapse, resulting in nose and mouth occlusion, which caused a secondary hypoxic phase. These results could have important implications for human drug users, as the combined use of benzodiazepines with potent opioids not only results in sustained brain hypoxia but creates conditions of loss of motor control which could result in asphyxia and death.This article is part of the Special Issue entitled ‘New Vistas in Opioid Pharmacology’.

Lab-on-a-screen-printed electrochemical cell for drop-volume voltammetric screening of flunitrazepam in untreated, undiluted alcoholic and soft drinks

Flunitrazepam, also known as “Rohypnol” or “Rophy” among other trade and street names, is an extremely potent benzodiazepine that is prescribed to treat severe insomnia. Due to these attributes, flunitrazepam, when is surreptitiously administered to an alcoholic or soft drink, is associated with “drug-facilitated sexual assault”. We report here for the first time, a low cost lab-on-a-screen-printed electrochemical cell (SPC) based on iron-sparked graphite working electrode modified with glucose oxidase (GOx) and glucose hydrogel droplets (GluHD) for the detection of flunitrazepam. Iron-spark modification increases the response of the sensor by ca. 3-fold compared with that of the plain electrode, while an in situ deoxygenation process, based on GOx-glucose enzyme reaction, depletes dissolved oxygen. As a result, the method enables interference free voltammetric measurements of the electro reduction of the nitro group of flunitrazepam at ca. −0.71 to −0.78 V vs. Ag printed pseudo reference electrode depending on the sample's matrix, and the detection of the drug at the sub-millimolar level. GOx/GluHD-FeSPC was directly applied to the drop-volume (∼60 μL) detection of flunitrazepam to a wide range of untreated and undiluted spiked samples (Pepsi cola®, Vodka, Whisky, Tequila, Gin, and Rum) of different acidity (pH 2.3–8.4), and alcohol content up to 40% v/v. Data demonstrate the excellent performance of the sensor for point-of-need screening of flunitrazepam and suggest that GOx/GluHD-FeSPC holds promise as an effective analytical tool to prevent phenomena of covert drug administration.

GABAA/benzodiazepine receptors in the dorsal periaqueductal gray mediate the panicolytic but not the anxiolytic effect of alprazolam in rats.

Although the etiology of panic disorder (PD) remains elusive, accumulating evidence suggests a key role for the dorsal periaqueductal gray matter (dPAG). There is also evidence that this midbrain area is critically involved in mediation of the panicolytic effect of antidepressants, which with high potency benzodiazepines (e.g. alprazolam and clonazepam) are first line treatment for PD. Whether the dPAG is also implicated in the antipanic effect of the latter drugs is, however, still unknown. We here investigated the consequences of blocking GABAA or benzodiazepine receptors within the dPAG, with bicuculline (5 pmol) and flumazenil (80 nmol), respectively, on the panicolytic and anxiolytic effects of alprazolam (4 mg/kg). Microinjection of these antagonists fully blocked the anti-escape effect, considered as a panicolytic-like action, caused by a single systemic injection of alprazolam in male Wistar rats submitted to the elevated T-maze. These antagonists, however, did not affect the anxiolytic effect of the benzodiazepine on inhibitory avoidance acquisition and punished responding, measured in the elevated T-maze and Vogel conflict tests, respectively. Altogether, our findings show the involvement of GABAA/benzodiazepine receptors of the dPAG in the panicolytic, but not the anxiolytic effect caused by alprazolam. They also implicate the dPAG as the fulcrum of the effects of different classes of clinically effective antipanic drugs.

Effect of Alprazolam on Redox Status in Renal Transplantation Donors and Recipients.

BACKGROUND Benzodiazepines are the most popular premedication drugs thought to act through the GABA/benzodiazepine receptor complex and alprazolam is one of the most potent benzodiazepines that have a quick onset. While there is a growing body of evidence supporting alprazolam in the amelioration of redox status in animals, no study has been performed concerning its antioxidant activity in humans. The purpose of this investigation was to determine the effect of alprazolam on redox status. MATERIAL AND METHODS This study was a four-group randomized controlled trial. Participants were recruited from Acibadem University Acibadem International Hospital and included a convenience sample of 82 donors and recipients undergoing renal transplantation. Patients were randomly divided into four groups. While donors and recipients in experimental groups (G1 and G3) were administered alprazolam 0.5 mg orally one hour before the operation, those in control groups (G2 and G4) were not. Serum advanced oxidative protein products, total thiol, free hemoglobin, ischemic modified albumin, and sialic acid levels at different time points were measured to evaluate the redox status. RESULTS All oxidative stress parameters were higher in the alprazolam premedication groups (G1, G3) at all time points than in the control groups (G2, G4). Basal values of oxidative parameters (at time point T1) in patients with CKD (G3, G4) were lower than in healthy donors (G1, G2). CONCLUSIONS Alprazolam premedication in donors and end-stage renal failure patients undergoing renal transplantation does not improve redox homeostasis but further experimental studies are needed.

Discovery of Epigenetic Regulator I-BET762: Lead Optimization to Afford a Clinical Candidate Inhibitor of the BET Bromodomains

The bromo and extra C-terminal domain (BET) family of bromodomains are involved in binding epigenetic marks on histone proteins, more specifically acetylated lysine residues. This paper describes the discovery and structure-activity relationships (SAR) of potent benzodiazepine inhibitors that disrupt the function of the BET family of bromodomains (BRD2, BRD3, and BRD4). This work has yielded a potent, selective compound I-BET762 that is now under evaluation in a phase I/II clinical trial for nuclear protein in testis (NUT) midline carcinoma and other cancers.

Physical health of patients with bipolar disorder

Bipolar disorder is a chronic, typically early onsetting group of mental disorders with a lifelong risk of relapse. It is characterized by recurrent periods of depression and pathologically elevated mood consisting of increased energy and activity during which patients may experience sleep loss, over-confidence, impaired concentration, extreme talkativeness, and engage in irresponsible risk-taking behavior. As a result, it is often problematic to undertake usual activities and maintain interpersonal relationships (World Health Organization [WHO], 2001). An estimated 2.4% of the world’s population suffer from some form of bipolar disorder, with a lifetime prevalence of 0.6% for bipolar I disorder and 0.4% for bipolar II disorder, while 1.4% of the total population has a lifetime prevalence of subsyndromal bipolar disorder (Merikangas et al., 2011). Bipolar disorders are categorized into bipolar I and bipolar II depending on a patient history of major depressive and hypomanic episodes only (bipolar II), or depressive and manic episodes in addition to hypomanic and mixed episodes (bipolar I). Subsyndromal symptoms may be diagnosed as bipolar disorder not otherwise specified. Patients with bipolar disorder encounter many difficulties in leading a normal lifestyle, even with the support of family, friends and carers, and therefore tend to have a low quality of life (QoL), which is powerfully influenced by two factors: the nature of mental illness itself and treatment-related comorbidities. Features of social disability that may trouble patients with bipolar disorder include problems in developing and sustaining friendships and difficulties in maintaining intimate relationships with a partner. Furthermore, the inability to manage money, housework, and coping with an emergency (Kai and Crosland, 2001) impedes a normal lifestyle. Possibly as a consequence of poor QoL, “self

2126 – How low dose of propranolol can induce a manic episode? case report of an unexpected side effect

Propranolol prescribed by physicians in various fields. The extensive use of beta adrenergic antagonists are their various side effects such as nausea, vomiting, diarrhea, constipation, agitation and confusion, Sleep disorders, nightmares, depression and anxiety auditory hallucination. Also a case of induction of mania phase due to discontinuing propranolol has been reported. A 11 year old boy was admitted with the diagnosis of Bipolar I disorder. Patient was started on 200 milligrams of Sodium Valproate twice daily and 1 miligram of Respridone twice daily. During the next 2-3 weeks his symptoms were gradually relieving and after 1 month patient left the psychiatric ward symptom free. At the one-month follow-up patient was still without any symptoms but had developed mild tremor and 10 milligrams of Propranolol was prescribed. A week later patient accompanied by euphoria, restlessness, insomnia and increased energy after discontinuing it the symptoms had waned. He toke propranolol again but in a lower dose of 10 milligrams. Interestingly after taking a single dose of 10 milligrams propranolol patient developed the same symptoms. The symptoms were relieved by discontinuing the medication. Low doses of potent benzodiazepines were used to control tremor, which was a successful strategy. The patient with the diagnosis of BMD, who contrary to our expectations developed symptoms of manic episode after taking low doses of Propranolol. We propose that clinicians take into consideration proper percussions before prescribing this drug to patients with mood disorders.

ChemInform Abstract: Anxiolytic Properties of Certain Annelated (1,2,4)Triazolo(1,5-c) pyrimidin-5(6H)-ones.

Modification of the benzodiazepine (BZ) receptor binding template 2-aryl[1,2,4]triazolo[1,5-c]quinazolin-5(6H)-one by replacement of the annelated benzene ring with various alicyclic and heterocyclic moieties led to novel structures with potent BZ receptor binding affinity. High affinity was found in some cycloalkyl-annelated [1,2,4]triazolo[1,5-c]pyrimidin-5(6H)-ones and in some 7,8,9,10-tetrahydropyrido[3,4-e][1,2,4]triazolo[1,5-c]pyrimidin- 5(6H)-ones, in which the degree of activity was strongly dependent on the N-substituent in the 9-position. Nine compounds with BZ receptor IC50 binding affinity values equal or superior to diazepam were evaluated in secondary screening. One of these, 9-benzyl-2-phenyl-7,8,9,10-tetrahydropyrido[3,4-e] [1,2,4]triazolo[1,5-c]pyrimidin-5(6H)-one, showed good activity in rats as a potential anxiolytic agent without sedative liability. However, it increased the rotorod deficit produced by ethanol at anxiolytic doses, an indication of alcohol interaction. Thus, none of the compounds showed an advantage over CGS 9896 (Yokoyama et al. J. Med. Chem. 1982, 25, 337-339), which is free of sedative and alcohol interaction potential as measured by the test procedures described.

Protective effect of SSR180575, a potent and selective peripheral benzodiazepine ligand, on TNF-α induced PMN apoptosis in whole human blood

Protective effect of SSR180575, a potent and selective peripheral benzodiazepine ligand, on TNF-α induced PMN apoptosis in whole human blood

ChemInform Abstract: Chromatographic Screening Techniques in Systematic Toxicological Analysis

A review of techniques used to screen biological specimens for the presence of drugs was conducted with particular reference to systematic toxicological analysis. Extraction systems of both the liquid-liquid and solid-phase type show little apparent difference in their relative ability to extract a range of drugs according to their physio-chemical properties, although mixed-phase SPE extraction is a preferred technique for GC-based applications, and liquid-liquid were preferred for HPLC-based applications. No one chromatographic system has been shown to be capable of detecting a full range of common drugs of abuse, and common ethical drugs, hence two or more assays are required for laboratories wishing to cover a reasonably comprehensive range of drugs of toxicological significance. While immunoassays are invariably used to screen for drugs of abuse, chromatographic systems relying on derivatization and capable of extracting both acidic and basic drugs would be capable of screening a limited range of targeted drugs. Drugs most difficult to detect in systematic toxicological analysis include LSD, psilocin, THC and its metabolites, fentanyl and its designer derivatives, some potent opiates, potent benzodiazepines and some potent neuroleptics, many of the newer anti-convulsants, alkaloids colchicine, amantins, aflatoxins, antineoplastics, coumarin-based anti-coagulants, and a number of cardiovascular drugs. The widespread use of LC-MS and LC-MS-MS for specific drug detection and the emergence of capillary electrophoresis linked to MS and MS-MS provide an exciting possibility for the future to increase the range of drugs detected in any one chromatographic screening system.

ISIDA - Platform for Virtual Screening Based on Fragment and Pharmacophoric Descriptors

In this paper we illustrate the application of the ISIDA (In SIlico design and Data Analysis) software to perform virtual screening of large databases of compounds and reactions and to assess some ADME/Tox properties. ISIDA represents an ensemble of tools allowing users to store, search and analyze the data, to perform similarity searches in large databases of molecules and reactions, to build and validate QSAR models, and to generate and screen virtual combinatorial libraries. It uses its own descriptors (substructural molecular fragments and fuzzy pharmacophore triplets). Workflow can be easily organized by combining different ISIDA modules. Several examples of ISIDA applications (similarity search of potent benzodiazepine ligands with FPT, QSAR modeling of aqueous solubility, aquatic toxicity, tissue-air partition coefficients, anti-HIV activity, and screening of the “Chimiotheque Nationale” Database), are discussed. Particular attention is paid to mining reaction databases using Condensed Reaction Graphs approach.

Characterization of 1′-Hydroxymidazolam Glucuronidation in Human Liver Microsomes

Midazolam is a potent benzodiazepine derivative with sedative, hypnotic, anticonvulsant, muscle-relaxant, and anxiolytic activities. It undergoes oxidative metabolism catalyzed almost exclusively by the CYP3A subfamily to a major metabolite, 1'-hydroxymidazolam, which is equipotent to midazolam. 1'-Hydroxymidazolam is subject to glucuronidation followed by renal excretion. To date, the glucuronidation of 1'-hydroxymidazolam has not been evaluated in detail. In the current study, we identified an unreported quaternary N-glucuronide, as well as the known O-glucuronide, from incubations of 1'-hydroxymidazolam in human liver microsomes enriched with uridine 5'-diphosphoglucuronic acid (UDPGA). The structure of the N-glucuronide was confirmed by nuclear magnetic resonance analysis, which showed that glucuronidation had occurred at N-2 (the imidazole nitrogen that is not a part of the benzodiazepine ring). In a separate study, in which midazolam was used as the substrate, an analogous N-glucuronide also was detected from incubations with human liver microsomes in the presence of UDPGA. Investigation of the kinetics of 1'-hydroxymidazolam glucuronidation in human liver microsomes indicated autoactivation kinetics (Hill coefficient, n = 1.2-1.5). The apparent S(50) values for the formation of O- and N-glucuronides were 43 and 18 microM, respectively, and the corresponding apparent V(max) values were 363 and 21 pmol/mg of microsomal protein/min. Incubations with recombinant human uridine diphosphate glucuronosyltransferases (UGTs) indicated that the O-glucuronidation was catalyzed by UGT2B4 and UGT2B7, whereas the N-glucuronidation was catalyzed by UGT1A4. Consistent with these observations, hecogenin, a selective inhibitor of UGT1A4, selectively inhibited the N-glucuronidation, whereas diclofenac, a potent inhibitor of UGT2B7, had a greater inhibitory effect on the O-glucuronidation than on the N-glucuronidation. In summary, our study provides the first demonstration of N-glucuronidation of 1'-hydroxymidazolam in human liver microsomes.

Venlafaxine extended release (XR) in the treatment of panic disorder.

Panic disorder is a chronic, recurrent illness, with a lifetime prevalence of about 5%. It is associated with substantial functional impairment, and studies suggest that treatment with medication alone (and no instruction in exposure to feared and avoided situations) is less than optimal. In fact, 40%-90% of patients in long-term follow-up studies in the late 1980s and early 1990s, treated with antidepressants or high potency benzodiazepines alone, remained somewhat symptomatic. Venlafaxine extended release (XR) was effective and well tolerated in both the short-term and long-term treatment of panic disorder. In 12-week trials, venlafaxine XR was significantly more effective than placebo in achieving a panic-free state (54%-70% vs 34%-48%, p</=0.05), and was as effective as paroxetine. In addition, venlafaxine XR has been shown to produce significantly higher response and remission rates than placebo. Relapse rates were significantly reduced with ongoing venlafaxine XR treatment compared to switching to placebo (22% vs 50%, p</=0.001), in a 6 month study. Importantly, venlafaxine XR significantly improved patient quality of life and functioning, and was generally well tolerated.